Blackjack project fails to update Access database - vb.net

Question

I have a simple blackjack game that I am trying to get to update a database by adding 2 simple values to it. I want it to add the username and the players' score to the database.
After watching an online tutorial this is the code I tried:
Imports System.Data.OleDb
Public Class Form1
'for updating database
Dim provider As String
Dim dataFile As String
Dim connString As String
Dim myConnection As OleDbConnection = New OleDbConnection
Private Sub ButtonSaveScore_Click(sender As Object, e As EventArgs) Handles ButtonSaveScore.Click
provider = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source="
dataFile = "F:\Documents\Class Documents\CSC289 - K6A - Programming Capstone Project\Project\BlackJack\BlackJack\Scoreboard.accdb"
connString = provider & dataFile
myConnection.ConnectionString = connString
myConnection.Open()
Dim str As String
str = "Update [Scores] set [UserName] = '" & playerName & "',[Score] =' " & wins & "' where [ID] = NEW"
Dim cmd As OleDbCommand = New OleDbCommand(str, myConnection)
Try
cmd.ExecuteNonQuery()
cmd.Dispose()
myConnection.Close()
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub
I get the error:
one or more variables is not provided
The first time I hit the save button. The second time it breaks the application and it says that I "cannot adjust the files current state it is already open. It then highlights myConnection.ConnectionString = connString.

Answer 1

Consider implementing Using:
Sometimes your code requires an unmanaged resource, such as a file handle, a COM wrapper, or a SQL connection. A Using block guarantees the disposal of one or more such resources when your code is finished with them. This makes them available for other code to use.
Here is some sample code:
Using con As New OleDbConnection(connectionString),
cmd As New OleDbCommand(commandString, con)
con.Open()
cmd.ExecuteNonQuery()
End Using
This will handle the closing and disposing of your objects.
I would also consider using parameters to avoid SQL injection. See Bobby Tables for more information on this.
Here is some sample code:
Using con As New OleDbConnection(connectionString),
cmd As New OleDbCommand("UPDATE [Scores] SET [UserName] = ?, [Score] = ? WHERE [ID] = ?", con)
con.Open()
cmd.Parameters.Add("#Username", OleDbType.[Type]).Value = playerName
cmd.Parameters.Add("#Score", OleDbType.[Type]).Value = wins
'I've popped this into a parameter as I'm unsure what it is. I'll leave that for you to decide
cmd.Parameters.Add("#ID", OleDbType.[Type]).Value = "NEW"
cmd.ExecuteNonQuery()
End Using
Note that I have used OleDbType.[Type]. You will want to replace this with the data type you have specified for your columns.
With OleDb the order of your parameters is important, not the naming. Ensure that you create the parameters as they appear in your command as shown above.